ECOLOGICAL RESTORATION: METHODS, IMPORTANCE AND EXAMPLES - ENVIRONMENT - 2025

The ecological restoration is the recovery of the structure and function of a degraded ecosystem, returning to a previous condition known or estimated. This encompasses a set of procedures and techniques that depends on both the type of ecosystem and the degree of degradation it presents.

Among the methods used in ecological restoration are reforestation, secondary succession, biological corridors, translocations, introductions and reintroductions.

Ecological restoration in Australia. Source: Nick carson at English Wikipedia / Public domain

Reforestation to be considered an ecological restoration must include species typical of the ecosystem in question. In this sense, the recovery of a degraded area with a forest plantation does not qualify as ecological restoration.

Ecological restoration is important to remediate ecosystem degradation, recover endangered species, and ensure ecosystem services. Among these services are being a source of water, energy, oxygen, carbon sink, recreation and tourism.

Ecological restoration methods

There are various methods to carry out ecological restoration, which in turn have variants depending on the ecosystem to be restored. It is necessary to take into account that each ecosystem has its own structure and functions.

Therefore, ecological restoration is not just about reestablishing a vegetation cover or introducing other living organisms to the area. Furthermore, there are differences between the restoration of a natural ecosystem and one where human activity is a permanent part.

- Cancel degrading processes

The first step of any ecological restoration project is to stop or control the action of those degrading factors of the ecosystem. These can be, among others, periodic fires, pollution or human productive activities.

- Reforestation

The term reforestation is used in a broad sense to refer to the replacement of the vegetation removed from a given area.

Deforested or burned areas

Reforestation is an alternative in areas that have lost their tree or shrub cover due to deforestation or fires. In terms of ecological recovery, reforestation must be carried out with native species of the ecosystem to be recovered.

Reforestation. Source: Botaurus / Public domain

On the other hand, for it to be successful, it must be taken into account that the soil and humidity conditions are adequate. In a deforested or burned zone, the abiotic conditions of the area change, the soil erodes more rapidly and its depth decreases.

Similarly, the temperature increases, there is more solar radiation and less humidity. These new conditions must be taken into account to guarantee the survival of the individuals planted.

- Secondary succession

In conditions of high degradation of an ecosystem, covering large areas, reforestation is not enough for ecological restoration. In these cases, secondary succession may be more successful, although it is a slower and more laborious process.

Ecological succession is a natural process that consists of the progressive replacement of some communities by others until a climax or optimal condition. In this process, they first colonize fast-growing pioneer plants that create conditions for other more demanding species.

Secondary succession in a Mediterranean forest. Source: Xvazquez / CC BY (https://creativecommons.org/licenses/by/3.0)

In the case of secondary succession, an attempt is made to reproduce this process either by promoting it to occur naturally or by intervening directly. In the latter case, a cover species introduction plan is established, then pioneer plants and finally plants typical of the climax ecosystem.

- Biological corridors

One form of degradation is the fragmentation of habitats, that is, a large ecosystem is divided into patches without connections to each other. This alters the functions of the ecosystem as a whole and for some species it can pose a great risk of extinction.

Ecological corridor. Source: Chico1952 / CC BY-SA (https://creativecommons.org/licenses/by-sa/4.0)

To correct fragmentation, an ecological restoration strategy is the establishment of ecological corridors. These are restored areas that connect one fragment to another, allowing the movement of species along them.

- Translocations

This method is applied to animal species and consists of transferring individuals from one population to another. It is especially useful in conditions of habitat fragmentation, where some populations remain isolated and have greatly diminished.

It is also used to protect endangered species, moving them to an area with better conditions.

- Introductions and reintroductions

Sometimes degradation affects populations of specific species to a greater extent, which can drastically decrease or disappear. In these cases, introductions in order to reinforce affected populations and reintroductions when species have disappeared from an area are very effective.

- Traditional anthropic practices

The human being is a species and as such is part of the ecosystem, therefore the action of traditional communities shapes the landscape. In this sense, in some cases restoring an area to the pre-existing state, you must consider traditional indigenous practices.

Importance of ecological restoration

Ecosystems are subject to a permanent process of degradation due to human pressure. Ecological restoration emerges as a proposal that integrates awareness of the role of ecological balance with knowledge of the functioning of ecosystems.

Restore with ecological criteria allows to recover and conserve the essential functions and services that the ecosystem provides.

Conservation of biodiversity

By definition, the main positive impact of ecological restoration is the recovery and conservation of biodiversity.

Drinking water sources

Ecosystems are the source of drinking water, so their ecological restoration allows us to protect or recover this resource. The vegetation cover captures the environmental humidity, decreases runoff and promotes infiltration by feeding the aquifers.

Carbon sinks and climate regulators

The forests and jungles of the planet capture the environmental CO ₂ and retain it by using carbon in the conformation of their tissues. In this way they extract CO ₂ from the atmosphere, thus reducing the greenhouse effect that is causing global warming.

Likewise, they play an important role in regulating the water cycle and therefore rain patterns.

Economic activities

The ecological restoration of ecosystems recovers their potential as sources of economic benefits within the framework of sustainable use.

Tourism and recreation

A recovered ecosystem represents a tourist attraction and a site for healthy recreation. This brings benefits to public health and drives the economy around tourism activity.

Ecological and recreational tourism in natural areas is the main source of economic development in many regions.

Raw Materials

Ecological restoration allows ecosystem species to flourish that can provide diverse raw materials for wise use. Forests are a source of food, fibers, building materials and genetic resources that can be used under a sustainability criterion.

Examples

- Ecological restoration of bauxite mines

This is an interesting example because it allows us to see the evolution of the concept of restoration towards an ecological criterion.

Alcoa World Alumina Australia is a mining company that extracts bauxite (obtaining aluminum) in Willowdale and Huntly in the Darling Range, south-west Australia. For this, mining shafts are established that extend for tens of hectares.

This company has been practicing since 1966 the restoration of the areas once the mining exploitation ceases. This area of ​​southwestern Australia is characterized by forests of eucalyptus, especially jarrah (Eucalyptus marginata).

First projects

Restoration methods have been improving over the years, with the initial projects consisting of planting exotic pine species. In this sense, the restoration that was carried out was not strictly ecological.

Ecological restoration

Today this company applies ecological restoration criteria, rehabilitating an average of 550 hectares per year. For this, it seeks to restore the jarrah forest in conditions close to the original, guaranteeing its original functions and services.

The methods used mainly include reforestation and control of secondary plant succession. The program has been successful as the presence of all commonly found species in a jarrah forest has been confirmed without intervention in a reclaimed area.

- National Park

This example of ecological restoration stands out for the peculiarity of its approach, since it involves reestablishing traditional human activities in an area.

Original condition

This region of southern Canada is representative of the vast grasslands of North America. These are extensive areas covered with grasses and inhabited by animals such as the pronghorn (Antilocapra americana) and the grouse (Centrocercus urophasianus).

Grasslands National Park (Saskatchewan, Canada). Source: 1brettsnyder / Public domain

In this region, the indigenous people traditionally practiced grazing and controlled burning of the prairie. Due to the importance of this biome, it was decided to conserve the area by including it in the national park system.

issue

The conservation action caused a process of change of the original ecosystem because when grazing and burning were suspended, the prairie began to transform. Thus, traditional human disturbances were an important part of the original ecosystem.

Solution

Given this, an ecological restoration program was implemented that included the reestablishment of traditional indigenous practices of grassland management. On the other hand, bison (Bison bison) were reintroduced in the region.

Ecological restoration methods in this case included species reintroduction, revegetation, and anthropic practices.

References

1. Fulé, PZ, Covington, WW, Smith, HB, Springer, JD, Heinlein, TA, Huisinga, KD and Moore, MM (2002). Comparing ecological restoration alternatives: Grand Canyon, Arizona. Forest Ecology and Management.
2. Gálvez, J. (2002). Ecological restoration: concepts and applications. Bibliographic review. Rafael Landivar University, Faculty of Environmental and Agricultural Sciences, Institute of Agriculture, Natural Resources and Environment. Technical Document Series No. 8.
3. Harris, JA, Hobbs, RJ, Higgs, E. and Aronson, J. (2006). Ecological Restoration and Global Climate Change. Restoration Ecology.
4. Higgs, ES (1997). What is Good Ecological Restoration ?. What is a Good Ecological Restoration? Conservation Biology.
5. Jackson, LL, Lopoukhine, N. and Hillyard, D. (1995). Ecological Restoration: A Definition and Comments. Restoration Ecology.
6. Jackson, ST, and Hobbs, RJ (2009). Ecological Restoration in the Light of Ecological History. Science.
7. SER (Society for Ecological Restoration). Australia: Returning the Botanical Richness of the Jarrah Forest in Restored Bauxite Mines in Western Australia. As seen on Feb 20. 202. Taken from: https://www.ser-rrc.org/project/australia-returning-the-botanical-richness-of-the-jarrah-forest-in-restored-bauxite-mines-in-western-australia /
8. Wortley, L., Hero, J.-M. and Howes, M. (2013). Evaluating Ecological Restoration Success: A Review of the Literature. Restoration Ecology.